zabbix_agentd in ZABBIX 1.4.4 allows remote attackers to cause a denial of service (CPU and connection consumption) via multiple vfs.file.cksum commands with a special device node such as /dev/urandom or /dev/zero.
https://exchange.xforce.ibmcloud.com/vulnerabilities/41196
http://www.vupen.com/english/advisories/2008/0878
http://www.securityfocus.com/bid/28244
http://www.securityfocus.com/archive/1/489506/100/0/threaded